1. Field of the Invention
The present invention relates to the detection of radiating electromagnetic waves, and more particularly, the present invention relates to the detection and location of radiating sources, often low-frequency radiating electromagnetic sources operating within the near-field, using Poynting vector E and B field measurements.
2. Description of Related Art
Near-field radiation (NF) includes electric and magnetic fields that have a more static character (quasi-static) and are localized “near” the surface of objects, while far-field radiation (FF) also known as “normal radiation”, generally refers to propagating radiation. In general, all radiating objects have both NF and FF components; however, most conventional detection methods of radiating sources generally avail themselves to propagative components in the FF. A source of radiation generally has three components: the tangential electric field, Et, the radial electric field, Er and the tangential magnetic field, Ht. The Poynting Theorem itself generally states that for any superimposed electric and magnetic fields, there must be energy flowing in the medium. Thus, the accepted theory for radiating fields can be derived from an electric field E and a magnetic field H in a cross-product Poynting vector E×H=S (watts per meter squared).
All electric power systems that involve electricity generation, transmission and loads are subject to transmission loss. One form of loss that is virtually impossible to eliminate is the radiated field loss (NF & FF) that comes with changing loads or loads that respond to applied voltage in a nonlinear fashion in a power generation and utilization system. This is energy loss due to the non-ideal flow of electrical currents resulting in a radiated electromagnetic field that is highly dependent on the specifics of the generator and loads and the result of an imbalanced system. An isolated and remote power source such as a generator will always produce an electromagnetic field that can be detected at some stand-off range. The range, however, will be strongly dependent on the power utilization purpose and the specific layout of the generator and loads.
Accordingly, a need exists for novel methods and instrumentation to locate radiating sources, often low-frequency radiating sources within the near-field based on Poynting vector E and B field measurements. The present invention is directed to such a need.